When you are working with sterile medium, or liquids that need to be autoclaved in a bottle, take care that your bottle-top dispenser can be autoclaved directly attached to the bottle. It is then only necessary to attach a filter to the back hole of the device to maintain sterility after autoclaving. Another option is autoclaving of the bottle-top dispenser and the medium separately. The bottle-top dispenser is then mounted safely and sterile to the medium in a bio-safety cabinet.